Devices Extra-corporeal

L-asparaginase therapy with an extra-corporeal device in patients with malignant lymphoma has resulted in repeated remissions of metastases (242). This technique utilizes L-asparaginase covalentiy bound to the surface of a battery of plates contained in a portable chamber which has been inserted between an artery and vein. 

The phrase within or on the body as used in 201(h) of the Act does not include extra corporeal systems or the solutions used in conjunction with such equipment. Such equipment and solutions will be regulated as devices by CDRH. 

HPTS covalently inunobilized on cellulose granules and with a p, of 7.1 is now used as the pH indicator in the Gas Stat device (Cardiovascular Devices Inc.) for continuous measurements on the extra-corporeal circuit. The pH sensor is generally associated with pCOj and PO2 measurements in a single catheter [50], which consists of three 125-pm fibers with appropriate chemistries at their ends [51]. 

Polyacrylamide is used in a wide range of cosmetic products such as moisturizers, lotions, creams, self-tanning products, etc. Polyacrylamides were first used as an implantable carrier for sustained delivery of insulin to lengthen the life of diabetic rats. Since then, various drug delivery systems based on polyacrylamide have been developed. It is also used as a carrier for other bioactive macromolecules and cells to produce the desired effects. Polyacrylamide-chitosan hydrogels are biocompatible and are used for sustained antibiotic release. Polyacrylamide is also used in extra corporeal toxin-removing devices, which remove unwanted toxic substances and subsequently returns the detoxified component to the circulation effectively. The function of polyacrylamide in an extracorporeal toxin removal modality is to provide a support matrix for immobilization of the functional parts or ligands. 

In order to test the valve behavior in vivo, two prototypes were implanted in a sheep model (IMM, Paris) in mitral position. The procedure was done under extra-corporeal bypass circulation. The first animal remained alive for 12 h after implantation with satisfactory valve function. The death ensuing came from intrathoracic bleeding. However, the absence of thrombosis on both sides of the fabric surface could be observed once the device was explanted (see Fig. 16.38). The second animal was still alive after 8 weeks... 

The coupling of encapsulation technologies with cell culture techniques permits the extended use of these bioreactors with complex tissue systems such as islet clusters. Existing reactor systems are also useful in obtaining the basic transport and reaction kinetics parameters necessary to design the novel devices required for biomedical applications. In summary, the relevance of this work to the biotechnology and health care-based industries is in the development, of artificial organ systems, extra-corporeal devices to... 

NOTE A corporation stop is a chemical injection device that screws into a recirculating cooling waterline. It includes a nozzle assembly to disperse chemicals into the center of the line for even mixing (although sometimes a static mixer is a useful extra) and permits the removal of the injection check valve without the need to shut down the line. 

---